Open breast biopsy. A critical analysis.

A retrospective study of open breast biopsies performed from January 1, 1988 to December 31, 1988 was undertaken to compare the malignancy rate of the authors with that generally reported in the literature. This was done to determine if biopsy of mammographically demonstrated nonpalpable lesions had a favorable impact on outcome, and to identify factors with high relative risk or predictive value for malignancy. Office records of 518 patients who underwent breast biopsies were reviewed, 122 of which (23.6%) proved to be malignant. The malignancy rate for needle localized excisions of nonpalpable lesions was 17.5 per cent. Of these, 28 per cent were stage tumor in situ (TIS), 60 per cent stage 1, and 12 per cent stage 2. A higher percentage of palpable lesions were malignant than were nonpalpable lesions (29.0%). Of the palpable malignancies, 28 per cent were stage 1, 51 per cent stage 2, 13 per cent stage 3, and 8 per cent stage 4. Those who were older than 40 years of age yielded a significantly higher malignancy rate when compared with the less than 40 age group (28.6% versus 6.7%, P less than 0.001). Lesions that appeared on mammogram as nodules, calcium, or both had a higher malignancy rate than those where no lesion was identified (25.3% versus 14.2%, P less than 0.001). None of these factors alone or in combination ruled out malignancy. Biopsy of nonpalpable mammographically demonstrated lesions lead to detection of breast cancer at an earlier stage. Age greater than forty years, demonstrable lesion by mammogram, and palpable lesion were significant predictors of malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)